Should seniors qualify as living donors?

Robert Brown was healthy, willing and a good match: So why not give a kidney to his wife, who otherwise would need dialysis?

There was just one potential obstacle: Brown was 74, an age once unthinkable for a kidney donor.

For this retired psychologist from Columbia, Md., that wasn't an issue. "I didn't think about the age thing, not at all," Brown said of his decision two years ago to offer a kidney to his wife, Sue. She was 71 at the time and ill with Fabry disease, a rare genetic disorder that can lead to a harmful buildup of fat in the kidneys.

For the Browns' physicians, what counted was the couple's physiological age — how healthy and strong each was — rather than their chronological age.

"We feel very strongly that healthy older adults should receive organ transplants and be considered as organ donors," said Dorry Segev, an associate professor of surgery at the Johns Hopkins University School of Medicine, whose colleagues operated on the Browns.

Many of the nation's transplant centers agree, at least in part. More than half of them do not have upper age limits for kidney transplant recipients.

But physicians are conservative about living kidney donors: Nearly three-quarters of transplant centers have not accepted organs from people older than 70, according to Johns Hopkins research.

Caution makes sense because the long-term effects of kidney donation on older adults are unknown, Sameh Abul-Ezz, a professor of nephrology at the University of Arkansas for Medical Sciences, noted in a 2010 commentary in the journal Kidney International.

In 2011, 96 people age 65 and older served as living kidney donors in the United States, according to data from the United Network for Organ Sharing, which manages the nation's transplant system. Between 1990 and 2010, 219 men and women between the ages of 70 and 84 donated kidneys, according to an article published in 2011 by Segev and colleagues.

Where their organs go

Most commonly, these seniors gave the organs to middle-aged and older adults whom they know well, unlike the system that distributes kidneys from deceased donors anonymously. The usual recipients were their children (37 percent), spouses or partners (35 percent), siblings (14 percent) and other relatives and friends.

Data about medical outcomes when using older kidneys, while relatively scarce, are encouraging. In his 2011 study, Segev found that 93 percent of patients who received kidneys from live donors 70 and older were alive one year after transplant surgery, and 74.5 percent survived five years. As for patients who got kidneys from live younger donors, 96 percent were alive at one year and 83 percent at five years, a result considered statistically equivalent.

A separate report from Sandip Kapur and colleagues from New-York-Presbyterian/Weill Cornell Medical Center found that kidneys from living donors age 60 and older were equally likely to be going strong after five years as those from younger donors. No differences were observed in results for a subset of donors 70 and older.

A case for expansion?

These and other good results "argue for the expansion of older living-donor transplantation because this may represent an important solution to the organ shortage," Kapur and his colleagues concluded.

But other transplant experts such as Abul-Ezz are less hopeful, citing evidence raising red flags.

In one analysis of 12 studies, patients who received kidneys from older living donors were less likely to be alive five years after than patients transplanted with kidneys from younger donors. Also, organs that came from older living donors were more likely to fail during this time period than those from younger donors.

While short- and intermediate-term outcomes for older kidney donors are generally positive— Segev's study found that nearly 96 percent of living donors 70 and older survived five years after surgery — some experts worry that older donors might experience potentially harmful, age-related declines in the functioning of their remaining kidney. Long-term research examining this question has not been done.

Then there is the reality that surgery can present additional risks for older patients; this requires physicians to be especially careful about whom they deem fit to undergo transplant procedures.

Almost half of the 871,000 Americans with advanced kidney disease are older than 65, and rates of chronic kidney disease in this age group more than doubled between 2000 and 2008, according to the National Institutes of Health.

The harsh reality is that more than half of kidney transplant candidates over age 60 will die before receiving an organ from a deceased donor, researchers estimate.

That is why such experts as Kapur, Segev and Mikel Prieto, surgical director of the kidney and pancreas transplant program at the Mayo Clinic in Rochester, Minn., are trying to broaden the pool of potential living donors to include adults in their 60s and 70s.

Studies indicate that 10 percent to 20 percent of seniors who need a transplant would find living donors, many among people of their own age, if they looked, Segev said.

Proposed distribution changes

Kidneys from deceased donors are carefully rationed under rules established by the nonprofit United Network for Organ Sharing, or UNOS. Kidneys go to people who have spent the longest time on waiting lists and who are a good match, with provisions made for distributing organs to patients within the same region, when possible.

That method would change under a proposal from the UNOS' kidney transplant committee.

The proposal, released in September, has two main goals, according to John Friedewald, chair of the committee and associate professor of surgery-organ transplantation at Northwestern University Feinberg School of Medicine.

The first is to maintain access to transplantation for everyone on waiting lists, more than 94,000 people currently. The second is to better use the available organs. Slightly more than 7,400 kidneys were harvested from deceased donors in 2011, the last full year for which data are available.

Under the proposed plan, all kidneys from donors who have died would be ranked, based on their expected survival after implantation. (All kidneys do not function equally, and the age and health condition of a donor can affect an organ's longevity.) A similar ranking would be done for potential recipients. Then, the top 20 percent of kidneys — those with the greatest expected longevity — would be matched to patients expected to live longest after receiving the organ.

No system of formally ranking patients by likelihood of survival currently exists.

The approach favors younger patients with longer life expectancies, but computer simulations of the proposal show that "more than half of kidneys would still go to candidates older than 50," Friedewald said.

For the 80 percent of patients not placed in the top tier, the current allocation system would remain largely intact. However, kidneys with the lowest expected survival would be distributed more widely across the country, a move that could help older patients.

At present, more than 2,600 less-than-optimal kidneys from donors who have died are discarded each year, in part because surgeons prefer higher-quality organs but also because the current allocation system does not factor in potential recipients' age.

UNOS expects further refinements before a change would go into effect.

Kaiser Health News is an editorially independent program of the Henry J. Kaiser Family Foundation, a nonprofit, nonpartisan health policy research and communication organization not affiliated with Kaiser Permanente.